The present invention relates to an electrical connector.
A conventional electrical connector (a conventional connector) including a plurality of terminals held in a housing by being molded integrally is disclosed in Patent Reference. In Patent Reference, the housing of the connector includes a circumferential wall composed of a pair of sidewalls extending in a longitudinal direction thereof and a pair of end walls extending in a short direction or a direction perpendicular to the longitudinal direction.
The housing further includes a bottom wall provided at a lower end edge of the circumferential wall so as to cover a space surrounded by the circumferential wall from a lower direction and a protruding wall surrounded by the circumferential wall, extending in the longitudinal direction as well as protruding in an upper direction. A space is formed between the circumferential wall and the protruding wall opening in the upper direction as a receptacle recess portion for receiving a fitting portion of a mating connector.    Patent Reference Japanese Utility Model Publication No. 11-000099
In the conventional connector disclosed in Patent reference, the terminal is held in the housing at a position closer to the sidewall. The terminal includes an elastic arm portion at a free end portion thereof, extending along the protruding wall. The terminal includes a horizontal base portion, the elastic arm portion, a transition portion, a downward extending portion and a connecting portion. The horizontal base portion extends in the short direction of the housing along the bottom wall of the housing.
The transition portion is formed by being bent the horizontal base portion at a position closer to the protruding wall in the short direction. The elastic arm portion extends in the upper direction through the transition portion. The elastic arm portion includes a contact portion at an upper end thereof. The downward extending portion extends in the lower direction obliquely, from the horizontal base portion at a position closer to the sidewall in the short direction. The downward extending portion is held in the housing. The connecting portion extends horizontally from the downward extending portion to outside of the housing.
The protruding wall of the housing includes a terminal groove extending in a vertical direction and opening in the upper direction, on a side surface thereof. The terminal groove is situated where corresponding to the terminal in the longitudinal direction and accommodates the transition portion and the elastic arm portion of the terminal therein. The protruding wall further includes a vertical wall portion extending in the vertical direction on both ends thereof and between the terminal grooves next to each other, in the longitudinal direction. In addition, the bottom wall has a hole opening where corresponding to the terminal in the longitudinal direction and where being close to the protruding wall in the short direction thereof. The hole opening opens so as to penetrate the bottom wall in the vertical direction. The terminal groove communicates with outside of the connector through the hole opening.
The housing holds the terminal partially at a position closer to the sidewall of the horizontal base portion and at the downward extending portion with a boundary region between the sidewall and the bottom wall thereof by being molded integrally. The terminal groove of the housing accommodates the transition portion and the elastic arm portion of the terminal so as to have a space from a groove bottom surface of the terminal groove in the short direction. Thereby, the elastic arm portion is capable of elastic displacement by bending toward the groove bottom surface in the short direction.
The transition portion and the elastic arm portion are situated so as to have a space from inner side surfaces of the terminal groove in the short direction as well. The spaces generated between the surfaces of the terminal groove and the transition portion and the elastic arm portion of the terminal is quite narrow, since the terminal groove is partially occupied by the transition portion and the elastic arm portion.
In the conventional connector disclosed in Patent Reference, the bottom wall of the housing has the hole opening situated underneath of the transition portion and of a portion close to the protruding wall of the horizontal base portion. Therefore, the portion close to the protruding wall of the horizontal base portion and the transition portion are capable of elastic displacement in the lower direction as the horizontal base portion is bent. Accordingly, the transition portion is displaced elastically only in the lower direction while the elastic arm portion is displaced elastically toward both of the lower direction and the groove bottom surface as described above.
In the conventional connector disclosed in Patent Reference, when the housing and the terminal are molded integrally, it is normally assumed that an upper mold for providing the receptacle recess portion and the terminal groove of the housing is arranged from the upper direction, and a lower mold for providing the hole opening of the bottom wall of the housing is arranged from the lower direction. As described above, in the conventional connector in Patent Reference, the transition portion and the elastic arm portion of the terminal are situated in the terminal groove. In addition, the transition portion is not allowed to be displaced elastically toward the groove bottom surface of the terminal groove. Accordingly, the upper mold is not able to displace the transition portion so as to be apart from the groove bottom surface upon being molded integrally. Therefore, the space the transition portion and the elastic arm portion of the terminal generate against the terminal groove remains narrow. As a result, it is necessary that the upper mold has a portion being small enough to correspond to the space described above.
These days, downsizing of connectors is highly demanding. Accordingly, in general, the space described above in the longitudinal direction is often designed to be very narrow. Therefore, it is considerably difficult to manufacture the upper mold with the portion thereof as narrow as the space described above. In case that the upper mold is able to have the portion narrow enough to correspond to the space, the upper mold has a complicated shape, resulting in difficulty in production thereof and reducing strength of the portion thereof.
When the space is designed to be large enough to simplify the shape of the upper mold for the purpose of ease in manufacturing of the upper mold and of obtaining enough strength of the upper mold as retaining number of the terminal grooves and size of the housing in the longitudinal direction, in other words, density of the terminals, it is necessary to make the vertical wall portion narrower. As a result, the vertical wall portion reduces strength thereof. Accordingly, obtaining the upper mold with easier manufacturing process as well as maintaining the strength thereof and maintaining the strength of the vertical wall portion are contrary to each other. Furthermore, though both conditions are satisfied, it is not preferable to enlarge both of the space and the vertical wall portion in the longitudinal direction since the connector becomes larger in the longitudinal direction.
In view of the problems described above, an object of the present invention is to provide an electrical connector which enables both of the mold and the housing to maintain the strength thereof as well as simplifying the shape of the mold, without enlarging the connector in size in the longitudinal direction.
Further objects and advantages of the invention will be apparent from the following description of the invention.